1. Field of the invention
The invention relates to a method for detecting objects.
2. Description of the related art
Modern stereo methods, as well as distance measuring sensors such as PMD, Lidar or high-resolution radar, generate a three-dimensional image of the surroundings. From these data, the relevant objects, for example stationary or moving obstacles, can be extracted. In practical applications, the step from the raw data to the objects is very large and often leads to many heuristic special solutions. For this further processing, a compact abstraction involving a small data volume is therefore desirable.
Known methods of stereo image processing operate with non-dense stereo cards and directly extract objects using heuristics which are deemed suitable. In general, there is no abstraction level which supports this step.
From US 2007/0274566 A1, a method for the detection of pedestrians is known, in which an image of a scene in front of a vehicle is recorded. In this image, a speed and a direction of pixels representing characteristic points are then calculated. Coordinates of the pixels which are obtained in this process are converted into a plan view. In this process, it is determined whether the characteristic points represent a two-dimensional or a three-dimensional object. If the object is three-dimensional, it is determined whether the object is moving. On the basis of the change of the speed with which the object moves, it is determined whether the object is a pedestrian. In extracting the characteristic points, edges of the object are detected and eroded, thus determining the middle of the edge. The eroded edge is then once again extended, so that the edge has a predetermined width, for example three pixels, so that all of the edges of the object have an equal width.